I moved my residence, and home office along with it, in the middle of 2018.
1. Can I deduct the moving expenses on my Schedule C or 8829?
2. How should I prorate the moving expenses - using the H/O square footage ratio of the old house or the new house?
No, you can not deduct moving expenses. Beginning in 2018 moving expense deductions are only available in certain circumstance by military members. The link below has information that you may find useful.